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  1. For those who don’t speak much slang – “Take the piss” may be a reference to a related (and dated) idiomatic expression, piss-proud, which is a vulgar pun referring to the morning erections which happen when a man awakens at the end of a dream cycle (each about 90 minutes in length throughout the night) or may be caused by a full bladder pressing upon nerves that help effect an erection.”